Understanding Logarithmic Identities in Differential Equations

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HeLiXe
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This is related to differential equations, but I think my question has more to do with log identities than DE.

I keep seeing equations like

1/8 lny = t + c

simplified to get the solution

y = ce^8t

but I am unsure of the identity being used to get 1/8 into the exponent as 8. I already understand how everything else is simplified, just not this part. Thanks!
 
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Just multiply both sides by 8 and exponentiate both sides.

The other way to see this would be that [itex]1/8 ln(y) = ln(y^{{1}\over{8}})[/itex]
 
*facepalm* Thanks penguwino LOL
 
That'll be $5
 
I'll give you $25 :-p

I kept switching it over the entire semester and never understood why I was doing that loll. This is what happens when the "simple steps" are skipped in math -_-
 
Tattoo the logarithmic identities to your forearm. It's far more useful then some rose or star
 
^ But then to avoid being suspected of cheating, you'd have to wear full-sleeve shirts during your exams. And that sucks when your exams are seated outside during a heatwave :(
 
Pengwuino said:
Tattoo the logarithmic identities to your forearm. It's far more useful then some rose or star
I'll see if I can have them burned on my retina :D
Dr. Seafood said:
And that sucks when your exams are seated outside during a heatwave :(
That is so sadistic! -_- Who would ever do such a thing to an innocent student?
 
HeLiXe said:
I'll see if I can have them burned on my retina :D

Try to burn them behind your retinas.
That works even better! ;)


HeLiXe said:
That is so sadistic! -_- Who would ever do such a thing to an innocent student?

Oh, standard trick to flush out not-so-innocent students.
 
I like Serena said:
Try to burn them behind your retinas.
That works even better! ;)

If there was something behind my retinae it would work better :-p